Imaging techniques for the capture of objects have become very important in the most various fields of application. Typical fields of application include the imaging of organs for medical applications as well as material and component testing for industrial purposes. For example, an ultrasonic sensor for medical purposes is able to produce three-dimensional tissue images, thus enabling one to identify the contours of a tumor so that a targeted therapeutic intervention can be planned and performed. In order to capture the three-dimensional structure of the object, it is necessary to produce a plurality of two-dimensional sectional images which are staggered relative to each other and are then combined to produce a three-dimensional object image. In this regard, the quality of the three-dimensional object image depends on the accuracy with which the individual two-dimensional sectional images are combined. In order to combine the individual sectional images, it is necessary to determine the movement of the ultrasonic sensor relative to the object as said movement represents the positions and orientations of the individual sectional images relative to one another.
EP 0 961 135 B1 discloses a sensor system for recording ultrasonic sectional images which is provided with an ultrasonic probe equipped with a position sensor that allows correct positioning of the recorded sectional images when the ultrasonic probe is moved during recording. Due to the fact that the position sensor provides absolute positional data in a defined reference coordinate system, the movement of the ultrasonic probe can be taken into account when reconstructing a three-dimensional object image from the sectional images. A drawback of this system is that an object's own motion is not detectable by the position sensor when recording the sectional images as a motion of this type has no influence on the position of the ultrasonic probe. Consequently, relative movements between the ultrasonic probe and the object which are due to the object's own motion are not detected and are not taken into account when reconstructing the three-dimensional object image, which results in a poor image quality.